Masonry Magazine October 2004 Page. 32
Drills & BITS
Profiling Isn't Always a NASTY WORD
By Tom Inglesby
Anchoring is critical in many situations. With a little extra effort, those bolts will hold much better.
WHEN A STRAIGHT HOLE IS DRILLED IN MASONRY units for an expanding anchor, the anchor uses pressure to grip the wall of the hole. In some situations, that might not be adequate. Anyone who has had an anchor come lose or fail due to chipping or cracking masonry at the drilled point can understand there must be a better way.
Now there is a novel technique available to provide greater security and safety with anchor holes. Using a standard rotary drill or concrete coring machine, a specially designed diamond drill bit can create a profiled hole with cavities at various depths along the hole's shaft, allowing anchors to expand into the areas rather than only apply pressure against the hole's wall. Where wind, seismic events or engineering call for even better security, profiled holes can be used with a variety of non-traditional anchors to give much better performance.
Anyone who has had an anchor come lose or fail due to chipping or cracking masonry at the drille point can understand there must be a better way.
The Profiler bit from Cintec, a global company with North American offices in Washington, D.C., and Nepean, Ontario, is designed to work with a complete anchoring system from Cintec but can, according to Robert Lloyd-Reese, also be used with standard expanding anchors. Lloyd-Reese, Cintec North America's COO, doesn't recommend that approach, however.
"The bit works best when it's applied with the full Cintec system, obviously," he says. "While we can't recommend using common anchors, they will work in an emergency; they just won't take advantage of the profiled hole as well as our system will."
The Profiler bit can be used with pre-drilled holes created with rotary drills or hammers or holes cast into concrete. Anywhere an anchor is needed and the material is cementious, a profiled hole could add reliability and security to the anchoring process. This includes setting equipment on concrete when the gear vibrates a lot, high side anchoring of mast climbers and scaffolding, securing block, stone and brick façade material to poured or panel concrete, and especially in restoration work where century-old material can afford minimal anchoring potential.
30 Masonry
October 2004
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